Fabrication of integrated circuits (IC) in the semiconductor industry typically employs plasma processing to create and assist surface chemistry necessary to remove material from and deposit material to a substrate within a plasma processing chamber. Examples of plasma processing apparatus include a plasma CVD (Chemical Vapor Deposition) apparatus configured to deposit a thin film on a substrate, and a plasma etching apparatus configured to remove material from a substrate, which can include using an etch mask to define locations for removing material.
In general, such plasma processing apparatus form plasma under vacuum conditions by flowing a process gas into a processing chamber. Heated electrons in the plasma can have energy sufficient to sustain dissociative collisions and ionizing. As such, a specific set of gases under predetermined conditions (e.g., chamber pressure, gas flow rate, etc.) may be chosen to produce a population of charged species and/or chemically reactive species. These species may be suitable, for example, to a particular process being performed within the processing chamber.